1 files changed, 283 insertions, 0 deletions
diff --git a/kernel/core/kernel.cpp b/kernel/core/kernel.cpp
new file mode 100644
index 0000000..c2d1806
--- /dev/null
+++ b/kernel/core/kernel.cpp
@@ -0,0 +1,283 @@
+// ============================================================================
+// core/kernel.cpp - Kernel singleton implementation
+// ============================================================================
+
+#include <kernel/kernel.h>
+#include <kernel/kprint.h>
+
+using namespace kernel;
+
+// ── Static instance (lives in .bss, zero-initialized) ─────────────────────
+
+static Kernel g_kernel;
+
+Kernel& kernel::GetKernel() {
+    return g_kernel;
+}
+namespace {
+// ── Version string formatting ─────────────────────────────────────────────
+
+// TODO: move it to string lib
+// Hand-rolled integer-to-string (no sprintf in freestanding)
+static char* format_uint(char* buf, uint16_t val) {
+    if (val == 0) {
+        *buf++ = '0';
+        return buf;
+    }
+
+    char tmp[6];
+    int len = 0;
+    while (val > 0) {
+        tmp[len++] = '0' + (val % 10);
+        val /= 10;
+    }
+    for (int i = len - 1; i >= 0; i--) {
+        *buf++ = tmp[i];
+    }
+    return buf;
+}
+
+static void build_version_string(VersionInfo& ver) {
+    char* p = ver.string;
+    char* end = ver.string + sizeof(ver.string) - 1;
+
+    p = format_uint(p, ver.major);
+    if (p < end) *p++ = '.';
+    p = format_uint(p, ver.minor);
+    if (p < end) *p++ = '.';
+    p = format_uint(p, ver.patch);
+
+    if (ver.codename && p < end) {
+        *p++ = '-';
+        const char* s = ver.codename;
+        while (*s && p < end) {
+            *p++ = *s++;
+        }
+    }
+
+    *p = '\0';
+}
+
+// ── Command line helpers ──────────────────────────────────────────────────
+
+extern "C" size_t strlen(const char* s);
+
+// Check if a word (space-delimited token) is present in the command line.
+static bool cmdline_has(const char* cmdline, const char* token) {
+    size_t token_len = strlen(token);
+    const char* p = cmdline;
+
+    while (*p) {
+        // Skip leading spaces
+        while (*p == ' ') p++;
+        if (!*p) break;
+
+        // Find end of current word
+        const char* word = p;
+        while (*p && *p != ' ') p++;
+        size_t word_len = static_cast<size_t>(p - word);
+
+        if (word_len == token_len) {
+            bool match = true;
+            for (size_t i = 0; i < token_len; i++) {
+                if (word[i] != token[i]) { match = false; break; }
+            }
+            if (match) return true;
+        }
+    }
+    return false;
+}
+
+// Parse "key=<decimal>" from command line. Returns 0 if not found.
+static uint64_t cmdline_get_uint(const char* cmdline, const char* key) {
+    size_t key_len = strlen(key);
+    const char* p = cmdline;
+
+    while (*p) {
+        while (*p == ' ') p++;
+        if (!*p) break;
+
+        // Check if current word starts with "key="
+        bool prefix_match = true;
+        for (size_t i = 0; i < key_len && p[i]; i++) {
+            if (p[i] != key[i]) { prefix_match = false; break; }
+        }
+
+        if (prefix_match && p[key_len] == '=') {
+            const char* val = p + key_len + 1;
+            uint64_t result = 0;
+            while (*val >= '0' && *val <= '9') {
+                result = result * 10 + (*val - '0');
+                val++;
+            }
+            // Handle M/G suffixes
+            if (*val == 'M' || *val == 'm') result *= 1024ULL * 1024;
+            else if (*val == 'G' || *val == 'g') result *= 1024ULL * 1024 * 1024;
+            return result;
+        }
+
+        // Skip to next word
+        while (*p && *p != ' ') p++;
+    }
+    return 0;
+}
+
+static void copy_cmdline(char* dst, const char* src, size_t max_len) {
+    size_t i = 0;
+    for (; i < max_len - 1 && src[i]; i++)
+        dst[i] = src[i];
+    dst[i] = '\0';
+}
+
+} //!namespace
+
+// ── Kernel::init ──────────────────────────────────────────────────────────
+void Kernel::init(const BootInfo& boot_info) {
+    state = KernelState::Booting;
+
+    // Version info
+    version.major    = CONFIG_KERNEL_VERSION_MAJOR;
+    version.minor    = CONFIG_KERNEL_VERSION_MINOR;
+    version.patch    = CONFIG_KERNEL_VERSION_PATCH;
+    version.codename = CONFIG_KERNEL_VERSION_NAME;
+    build_version_string(version);
+
+    // Boot parameters — parse command line if provided
+    if (boot_info.cmdline) {
+        copy_cmdline(boot_params.cmdline, boot_info.cmdline, sizeof(boot_params.cmdline));
+        boot_params.verbose   = cmdline_has(boot_params.cmdline, "verbose");
+        boot_params.nosmp     = cmdline_has(boot_params.cmdline, "nosmp");
+        boot_params.noacpi    = cmdline_has(boot_params.cmdline, "noacpi");
+        boot_params.mem_limit = cmdline_get_uint(boot_params.cmdline, "mem");
+    }
+
+    // Log level — from boot params or compile-time config
+    if (boot_params.verbose) {
+        log_level = LogLevel::Debug;
+    }
+#ifdef CONFIG_DEBUG_VERBOSE_BOOT //TODO: fix it
+    else {
+        log_level = LogLevel::Debug;
+    }
+#endif
+
+    // Framebuffer (plain struct copy)
+    framebuffer = boot_info.framebuffer;
+
+    // Kernel load info
+    kernel_phys_base = boot_info.kernel_phys_base;
+    kernel_virt_base = boot_info.kernel_virt_base;
+    kernel_size      = boot_info.kernel_size;
+    hhdm_base        = boot_info.hhdm_base;
+
+    // Init Firmware
+    //TODO: when get heap fix it
+    if(boot_info.rsdp_address) {
+        tmp_acpitable[0].Init(boot_info.rsdp_address);
+        acpi = &tmp_acpitable[0];
+        dt = nullptr;
+    }
+    if(boot_info.fdt_address) {
+        tmp_devicetree[0].Init(boot_info.fdt_address);
+        dt = &tmp_devicetree[0];
+        acpi = nullptr;
+    }
+
+}
+
+// ── Boot data accessors ─────────────────────────────────────────────────── 
+//TODO: don't forget to remove FrameBuffer
+const FramebufferInfo&  Kernel::GetFramebuffer() const {
+    return framebuffer; 
+}
+
+PhysAddr Kernel::GetKernelPhysBase() const {
+    return kernel_phys_base;
+}
+
+VirtAddr Kernel::GetKernelVirtBase() const {
+    return kernel_virt_base;
+}
+
+uint64_t Kernel::GetKernelSize() const {
+    return kernel_size;
+}
+
+VirtAddr Kernel::GetHhdmBase() const {
+    return hhdm_base;
+}
+
+// ── Firmware subsystem accessors ─────────────────────────────────────────
+
+AcpiTables* Kernel::GetAcpiTables() const {
+    return acpi;
+}
+
+DeviceTree* Kernel::GetDeviceTree() const {
+    return dt;
+}
+
+// ── Accessors ─────────────────────────────────────────────────────────────
+KernelState Kernel::GetState() const {
+    return state;
+}
+
+const VersionInfo& Kernel::GetVersion() const{
+    return version;
+}
+
+const char* Kernel::GetArchName() const{
+    return arch::name();
+}
+
+// ── Boot params & log level accessors ─────────────────────────────────────
+
+const BootParams& Kernel::GetBootParams() const {
+    return boot_params;
+}
+
+LogLevel Kernel::GetLogLevel() const {
+    return log_level;
+}
+
+void Kernel::SetLogLevel(LogLevel level) {
+    log_level = level;
+}
+
+// ── State transitions ─────────────────────────────────────────────────────
+
+void Kernel::SetRunning() {
+    if (state == KernelState::Booting)
+        state = KernelState::Running;
+}
+
+void Kernel::SetHalt() {
+    if (state != KernelState::Panicked)
+        state = KernelState::Halted;
+}
+
+// ── Panic ─────────────────────────────────────────────────────────────────
+// ATM it's useless
+const PanicInfo& Kernel::GetPanicInfo() const {
+    return panic_info;
+}
+
+[[noreturn]] void Kernel::Panic(const char* msg, const char* file, const char* func, uint32_t line) {
+    state = KernelState::Panicked;
+
+    panic_info.message = msg;
+    panic_info.file    = file;
+    panic_info.line    = line;
+    panic_info.func    = func;
+    panic_info.cpu_id  = 0; // TODO: get actual CPU id when SMP is added
+
+    // Print panic banner — kcon may or may not be initialized yet
+    kcon::putchar('\n');
+    kcon::println("!!! KERNEL PANIC !!!");
+    kcon::kprintf("  %s\n", msg);
+    kcon::kprintf("  at %s:%s:%u\n", file, func, line);
+    kcon::putchar('\n');
+
+    arch::halt();
+}
+